Aphid Control on Cabbage Using Foliar Sprays, 1978

Abstract

Abstract ‘Superette Y. R.’ variety cabbage was field-seeded on Mar 10 at the TAMU Vegetable Res. Sta., Munday, TX. Plots consisted of 6 rows, 30-ft long, on 40-in centers (3 rows on each side of a row of overwintered cabbage) and were arranged in a randomized complete block design with 3 replicates. Endosulfan 75W was sprayed on Mar 19 at 2.0 lb ai/acre, in 14.0 gal water/acre, to control a severe infestation of flea beetles, Epitrix spp. A laboratory bioassay was begun on Apr 28 due to lack of aphid infestation. Five field leaves/treatment from plots sprayed 2 hours earlier at 27.4 gal water/acre were infested with 10 green peach aphids collected from kohlrabi. Counts were made 3 and 7 days after application. Leaves were reinfested after the 3-day count. A field infestation began May 12 and aphid numbers increased rapidly thereafter. The first foliar application was made on May 18 and the second on Jun 13. All sprays were applied with a pressurized hand-drawn sprayer equipped with cone nozzles (10X) which delivered 29.0 gal water/acre. Insect counts were made on 10 plants/plot chosen at random from the center 2 rows. Yield samples (0.001 acre) were taken from each plot on Jun 28. Percent control calculations for the bioassay and field tests were made according to the method of C. F. Henderson and E. W. Tilton, 1955, J. Econ. Entomol., 48:157-61. Duncan’s Multiple Range Test at the 0.05 probability level was used to determine differences between percentage control values.